Yes, you can.
There are two ways to add a link to a website in a survey.
You can use the "Finished URL" box in the invitation to enter an address that will redirect the participant to a website when the survey ends.
You can add an internet address to the invitation email inline by using this format:
[example link]( http://www.example.com/ )
This way, a URL will be added to the text that is clickable and will send the respondent to the site.
You can use this if you want to give the respondent information they might need before filling in the survey or something similar.